1. Field of the Invention
This invention deals with artificial sweeteners.
2. Description of the Art Practices
In recent years suitable substitutes for saccharin and cyclamates have been sought due to potential health consequences of overuse of these sweeteners.
Aspartame has been suggested as a replacement for all artificial sweeteners due to its sweetening properties and purported low toxicity levels. The use of aspartame is described in a bulletin of G.D. Searle & Co. through its subsidiary Searle Food Resources, Inc., Box 1045, Skokie, Ill. 60076 in an article entitled THE NUTRASWEET BREAKTHROUGH, Copyright 1982, Publication No. US 001-682 which is incorporated by reference. A portion of the publication indicates that aspartame loses its effectiveness due to breakdown of the components under conditions where hydrolysis may occur, particularly in the acid pH region. Further discussions of aspartame under the title ASPARTAME CLEARED FOR SOFT DRINKS was recently published at page 41 of the Food Chemical News, Vol. 25, No. 17 (July 4, 1983) which is a publication of Food Chemical News, Inc., 1101 Pennsylvania Avenue, S.E., Washington, D.C. 20003. The Food Chemical News article is also herein incorporated by reference.
The chemistry of cyclodextrin compounds is discussed in an article entitled CYCLODEXTRIN INCLUSION COMPOUNDS IN RESEARCH AND INDUSTRY by Wolfram Saenger at pages 344-362 of the publication ANGEW. CHEM. INT. ED. ENGL., Vol. 19 (1980). A further discussion of cyclodextrins is found in an article entitled FORMATION AND MOLECULAR DYNAMICS OF CYCLOAMYLOSE INCLUSION COMPLEXES WITH PHENYLANINE by Inoue and Miyata in the Bull. Chem. Soc. Jpn. Vol. 54, pages 809-816 (1981). Both of the aforementioned articles on cyclodextrins are herein incorporated by reference.
Japanese patent publication No. 56-2560 teaches and describes the use of beta-cyclodextrin in combination with a variety of sweetners including aspartame in order to produce a water-soluble solid sweetener. This publication indicates that by using beta-cyclodextrin in combination with sweeteners such as aspartame, that a water-soluble solid sweetener can be prepared which has desirable properties such as resistance to wear and tear. This reference also indicates that the solid sweeteners prepared by combining beta-cyclodextrin with other sweeteners are easily dissolved in water, easily tabletized or shaped, having excellent smoothness and crumbling properties. Thus, beta-cyclodextrin is used in this reference as a bulking agent for the preparation of a solid tabletized sweetener. Maruzen teaches that such solid sweeteners can be prepared by mixing and molding. The sweetener can then be transported or added into water for sweetening purposes.
It has now been discovered that cyclodextrin can be combined with aspartame under conditions which result in the stabilization of aspartame against hydrolysis. It is thus an object of the instant invention to describe a composition of matter containing aspartame in a specific structural relationship with cyclodextrin (an inclusion complex) which serves to reduce hydrolysis and gives more stability to the aspartame. A further object of the instant invention is to provide a method whereby the protection of aspartame against hydrolysis can be optimized. A further object of the instant invention is to describe a method for producing the inclusion complex of cyclodextrin and aspartame in a solid form which preserves the aspartame under adverse storage conditions such as heat, humidity, light, and acidity. Other objects will become apparent as this description proceeds.